The antenna is any object that receives radio signals and inputs them to a receiver or
emits radio signals from a transmitter. As a result, during emergency or makeshift
conditions, anything from bed springs to barbed wire fences can be used as an antenna.
However, antennas are critical to good reception and transmission and the following
sections show how to build suitable antennas and what types might work best for your
situation.
It would be reasonable to expect that HF antenna systems would all be
somewhat similar. In most low-space or mobile situations, the basic HF antenna
systems are unwieldy and you would not be able to install one. However, these
antennas are somewhat flexible (from a theoretical and a physical point of view)
and by following or altering some of the basic designs, you can create systems
that will suit your needs in almost any situation. The following list shows some
of the circumstances where different types of antennas are required.
Base-station operations require the most basic full-sized antennas. Because most base stations include some
real estate, large wire antennas can usually be installed without problems.
Mobile operations require antennas that can be mounted on a moving vehicle. This rules out wire antennas.
Mobile antennas are typically derivations of the whip vertical antennas, although some others have been used,
depending on the vehicle used and the circumstances. SGC makes a full line of mobile high performance antennas,
such as the SG-303.
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The SGC Building, 13737 S.E. 26th St. Bellevue, Washington 98005 USA
P.O. Box 3526, 98009 Tel: (425) 746-6310 Fax: (425) 746-6384
© 1997 SGC Inc.
HF ANTENNAS, FEEDLINES, AND GROUNDS
OPERATING ENVIRONMENT
In emergencies,
anything from bed
springs to wire
fences can be used
as an antenna.
BASE
MOBILE
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